Azo dyestuffs and their manufacture



Patented Mar. 16, 1937 UNITED sures AZO DYESTUFFS AND THEIR MANUFACTURE Adolf Krebser, Riehen, near Basel, Switzerland, assignor to the firm J. R. Geigy, A. 6., Basel,

Switzerland N Drawing. Application October 16, 1935, Serial No. 45,359. In Germany November 10, 1934 8 Claims.

20 and reducing the nitro-naphthol-sulphonic acid thus formed [see Ruggli, Helv. chim. acta XII,

1929, page 1034].

The following examples and tables illustrate the invention:-

Example 1 16.8 kilos of 6-nitro-4-methyl-2-aminophenol are ,diazotized in the usual manner and coupled in a solution, feebly alkaline with sodium car- 30 bonate, with 28.4 kilos of 2-acetylamino-6-hydroxynaphthalene-8-sulphonic acid, made by acetylating by known methods 2-amino-6-hydroxynaphthalene-S-sulphonic acid. When coupling is complete the dyestuff is filtered and dried. It is a 35 black powder soluble in dilute acetic acid to a violet solution, in dilute sodium carbonate solution to a blue solution and is concentrated sulphuric acid to a blue-red solution. It dyes wool in an acid bath blue, which becomes, when after- 0 chromed, a blue-grey of characteristic properties of fastness.

Example 2 If in Example 1 or 2 there is substituted 2- chloroacetylamino 6 -hydroxynaphthalene-8-sulphonic acid for the 2-acetylamino-derivative, dyestuffs having similar properties are obtained.

Example 3 23.4 kilos of 4-nitro-2-aminophenol-6-sulphonic acid are diazotized as usual. The diazonium solution is added to a solution, alkaline with sodium carbonate, of 34.3 kilos of Z-benzoylamino-G-hy- 10 droxynaphthalenee8-sulphonio acid, made by benzoylating 2 amino-6-hydroxynaphthalene-8- sulphonic acid in presence of sodium acetate by known methods. When coupling is complete the dye-stuff is filtered; it is a black powder, soluble in aqueous acetic acid to a red solution, in sodium carbonate solution to a violet solution and in concentrated sulphuric acid to a blue-red solution.

It dyes wool in an acid bath blue, which on afterchroming becomes olive. The chromed dyeing has very good properties of fastness.

Example 4 14.4 kilos of 4-chloro-2-aminopheno1 are diazotized in the usual manner and the diazonium solution is run into one of 34.3 kilos of 2-benzoy1- amino-6-hydroxynaphthalene-8-sulphonic acid, obtained as described in Example 3, in 200 litres of water containing 14 kilos of anhydrous sodium carbonate and 100 litres of pyridine. When coupling is complete the separated dyestufi is filtered and dried. It is a black-violet powder, which dissolves in aqueous acetic acid to a red solution, in a solution of sodium carbonate to a blue solution and in concentrated sulphuric acid to a violet solution; it dyes wool in an acid bath red, which on after-chroming, becomes fast blue.

Example 5 15.4 kilos of 5-nitro-2-aminophenol are diazotized in the usual manner and the diazonium solution, the mineral acid in which has been buffered with sodium bicarbonate, is allowed to flow into a solution of 39.5 kilos of Z-para-toluenesulphonylamino- 6 -hydroXynaphthalene-8- sulphonic acid, (made by the action of toluenesulphochloride on 2-amino-6-hydroxynaphthalene-8-sulphonic acid in an acid solution) in 250 litres of water containing 10 kilos of sodium bicarbonate and 100 litres of pyridine.

When coupling is complete the dyestuff is filtered; it is a black powder, soluble in aqueous acetic acid to a blue-red solution, in a sodium carbonate solution to a green-blue solution and in concentrated sulphuric acid to a blue-red solu- 5. A process for the manufacture of orthotion. It dyes wool in an ac1d bath violet, which on after-chromlng becomes greemsh-grey. hydroxyazo-dyestuffs capable of being chromed,

Solution in water containing Dyeings on wool Solution in con- Diazo component Coupling component S d ceililtrated s l- 0 mm carp uric aci Acetic acid bonate Solution Acid Chromed (1) 4-chloro-2-emino-phenol 2-acetyl amino 6 hy- Red. Violet. Violet. Red-violet. Blue-grey.

dreary-naphthalene 8 sulphonic acid. (2) 4,6 glichlloro 2 -amino Violet. Blue-red. Violet. Grey.

p eno (3) 4- it oi p Red-violet. Blue'red. Violet. Olive. (4) 5-nitro-g-am mo-phenol. Blue. Blue-red. Violet. Greenish-grey. (5) Picraunc acid Violet. Blue-red. Violet. Olive. (6) 2-amin0-pl1en01- -Su Blue. Blue-red. Blue-red. Bluc-violet.

phonic acid. (7) fi-methyl-Z-arqmo-phedo Red. Blue. Blue-red. Red. Red-blue.

nol-4-su1phon1c acid. (8) 4-nitro-2-amino phenol- ..do Violet. Red. Blue-red. Blue-grey. Olive.

fi-sulphonic acid. (9) fi-nitro-2-allf ino p enoldo Blue-red. Blue. Blue-red. Blue. Grey. 4-sulphon1c ac d. (10) 4,6-dichloro-ammc-pl1e- 2-benzoyl-ainino-6-hy- Blue-red. Blue. Violet. Blue-violet. Blue-grey.

nol. droxy-naphthalene-sv sulphonic acid. (11) 4-nitro-2-am no-ph n0L- do Yellow-red. Violet. Blue-red. Violet. Olive-grey. 2) r -amino-pheno1 Violet. Blue. Blue-red. Blue. Greenish-grey (l3) 6-nitro-4-inethy1-2- Red. Blue. Violet. Blue-violet. Blue-grey.

amino-phenol. (i4) 4-methyl-2-am no-phe- Blue-red. Violet. Blue-red. Red-violet. Grey-blue.

nol-li-sulphomc acid. (15) 4-cliloro-2-am no-phe- Blue-red. Violet. Violet. Red. Blue.

1101-6-5111ph01'll0 acid. (16) 6-nitro-2-amino -phenol- Blue-red. Blue. Blue-red. Blue. Grey. 4-sulphonicecid. (17) 4-chlom-2-an1ino-plienoL. z-pare-toluene-sul- Blue-red. Blue. Violet. Blue-red. Blue-violet.

phonylanlino-fi-hydroxy-naphthalene-B- sulphonic acid. (18) 6 nitro 4 methyl 2 do Blue-red. Blue. Blue-red. Violet. Blue.

amino-phenol.

(19) 4 chloi'o 2 amino do Blue-red. Blue. Violet. Red-violet. Blue-grey.

phenol 6 sulphonic ac (20) 6 nitro 2 emin0 -.do Blue-red. Blue. Blue-red, Blue. Grey.

plieinol 4 sulplionic 801 What I claim is:-

1. A process for the manufacture of orthohydroxyazo-dyestuffs capable of being chromed, consisting in coupling an ortho-hydroxy-diazom'um compound with an N-acyl-den'vative of 2-amino-6-hydroxynaphthalenc-8-sulphonic acid.

2. A process for the manufacture of orthohydroxyazo-dyestufis capable of being chromed, consisting in coupling an ortho-hydroXy-diazonium compound with a Z-acetylamino-G-hydroxynaphthalene-8-sulphonic acid.

3. A process for the manufacture of orthohydroXyazo-dyestuffs capable of being chromed, consisting in coupling an ortho-hydioxy-diazonium compound with 2-benzoylamino-6-hydroxynaphthalene-8-sulphonic acid.

4. A process for the manufacture of orthohydroxyazo-dyestuffs capable of being chromed, consisting in coupling an ortho-hydroxy-diazonium compound with Z-paratoluenesulphonyh amino-6-hydroxynaphthalene-8-sulphonic acid.

aminophenolwith 2-para-toluenesulphonylamino- 6-hydroxynaphthalene-8-sulphonic acid.

8. Ortho-hydroxyazo-dyestuffs from an orthohydroXy-diazonium compound and an N-acylderivative of 2-amino-6-hydroxynaphthalene-8- sulphonic acid, said dyestuffs yielding dyeings which, when chromed, have remarkable properties of fastness.

ADOLF KREBSER.

2-benzoylamino-6-hydroxywith 2-acetylamino-6- 

